K&N

[Andrew]

Folk on here have been very helpful with my quest for information on using filters for 48 IDA Weber carbs.

Here's a next installment, posted in a better place than the "Show me your pictures thread".

To improve my knowledge, I first purchased, and am busy reading a copy of "How to rebuild your VW Air Cooled Engine" by Tom Wilson, it seems pretty comprehensive and as good a place as any to start.

Tom's book spends the first chapter asking the question "Time to Rebuild?" Tom's goes on to give reasons why a rebuild might be needed, he seems to give plenty of space to air filters, good engine seals, air filters, oil changes, oil and air filters, oil consumption, loose cylinder heads, air filters, over heating, air filters and so on...

Seems there's four choices.
 

• Fit filters that are designed for engine bays that are tight for space, there is evidence on here and other places on the Internet that these things can be a fire risk as the filter element is too close to the carb/stacks.
• Fit pop off filters or socks for longer journey's, less of a fire risk but accept they they will strangle the engine
• Do nothing and learn how to strip the carbs to keep them clean and risk possible engine problems later on.
• Fit K&N filters that don't restrict flow. The $64 million question is....will they go under the deck lid?

So, I have made myself a K&N 83mm Weber Filter to see if it will fit.

Here is my K&N filter, please don't laugh.

Anyone care to take guess does it fit under the deck lid? I have short manifolds.....

[Zach Gomulka]

Check this out, the interesting stuff starts at 13:09

https://www.youtube.com/watch?v=vFboNbYx0BI

[Andrew]

Yep. strangle the engine, 2/3 is by quite some amount.

Andrew

[Jeff68]

I was thinking about  putting air filters on the IDA's on my engine too. I like the billet Berg stacks that are made for K&N filters that go with them (also sold by the Berg's). I've never seen anyone use these and I don't know why. Maybe not considered Cal-Look?  They are not cheap and I'm not sure they fit under the decklid either. If you search on the Samba or on Berg's website you will find them.

[Andrew]

I was thinking about  putting air filters on the IDA's on my engine too. I like the billet Berg stacks that are made for K&N filters that go with them (also sold by the Berg's). I've never seen anyone use these and I don't know why. Maybe not considered Cal-Look?  They are not cheap and I'm not sure they fit under the decklid either. If you search on the Samba or on Berg's website you will find them.

These ones?

http://www.geneberg.com/product_info.php?cPath=261&products_id=883

Or the shorter ones.

http://www.geneberg.com/product_info.php?cPath=261&products_id=888

The cleaner they both point to is.

http://www.geneberg.com/product_info.php?products_id=874

I am assuming you need 4 of each.

I don't know if they're considered Cal Look or not, anyone care to comment?

[Andrew]

Here's some pictures I found on the Samba, sadly nobody replied to the poster's question asking if anyone had any experiences with these stacks and filters.





Andrew

[Bruce]

Check this out, the interesting stuff starts at 13:09

https://www.youtube.com/watch?v=vFboNbYx0BI

Sorry for going way off topic, but have a look at the Chevy II at 9:17.  That car is an incredible piece of drag racing history. Notice how the rear axle and wheel cutouts are moved forward for better weight distribution?  This car and others doing that same type of mod is what started the NHRA Funny Car class.

[Andrew]

Check this out, the interesting stuff starts at 13:09

https://www.youtube.com/watch?v=vFboNbYx0BI

Sorry for going way off topic, but have a look at the Chevy II at 9:17.  That car is an incredible piece of drag racing history. Notice how the rear axle and wheel cutouts are moved forward for better weight distribution?  This car and others doing that same type of mod is what started the NHRA Funny Car class.

Cool. I'll have another look for that.

[Jeff68]

Andrew......Yes, those are the stacks and filters I was talking about from the Bergs. They do give measurements on how tall the stacks and filters are so I suppose you could measure and try to see if they will fit. I haven't seen anyone run these stacks and filters though and I wonder why?

[Zach Gomulka]

Andrew......Yes, those are the stacks and filters I was talking about from the Bergs. They do give measurements on how tall the stacks and filters are so I suppose you could measure and try to see if they will fit. I haven't seen anyone run these stacks and filters though and I wonder why?

Because, "Filters are for people that want to make their IDA's look stupid"

Mark Herbert

 

[Jeff68]

^^^^ Yeah I know adding filters may not look as cool. I also talked with a guy that has a successful VW performance shop (30 years +, and a past vw drag racing record holder) who had run IDA's on street cars about this. He told me he really hasn't seen adverse wear from not using filters on IDA equipped VW's.  He even agreed that it doesn't seem to make sense but from his experience this is what he's seen.  As far as the Berg filters.....at least they don't make the carb stacks look like microphones  . IF I was going to run filters these would be the only solution for me.

[Zach Gomulka]

^^^^ Yeah I know adding filters may not look as cool. I also talked with a guy that has a successful VW performance shop (30 years +, and a past vw drag racing record holder) who had run IDA's on street cars about this. He told me he really hasn't seen adverse wear from not using filters on IDA equipped VW's.  He even agreed that it doesn't seem to make sense but from his experience this is what he's seen.

Exactly. New cars have filters because they don't know where you'll be driving them. IDA equipped VW's are a different beast- in most cases driven a lot less, taken much better care of, and not rallied down dirt roads. I don't see any downsides running without filters in our application.

[Jim Ratto]

One thing I wonder about is when I see guys running 48IDA's, on VW's or V8's and they've capped the air horns with those flat foam/metal filters. I tried those a long time ago and immediately took them off. I didn't realize it at the time, but how do those allow for fuel stand off/reversion that happens with Webers on VW? They can't.

[Zach Gomulka]

One thing I wonder about is when I see guys running 48IDA's, on VW's or V8's and they've capped the air horns with those flat foam/metal filters. I tried those a long time ago and immediately took them off. I didn't realize it at the time, but how do those allow for fuel stand off/reversion that happens with Webers on VW? They can't.

Ding ding ding!

My buddy was dialing in/jetting a fresh 2276 at Gary B's shop a few years ago. He drove it from AZ for the Classic weekend but was endlessly trying to perfect it Anyway, he had those thin little pantyhose type filters over the stacks (no metal or foam). LM2 installed to monitor changes. Same as the video above, he removed the filters and it went lean, go figure. He's never used them since. They may flow air just fine, but not when soaked with fuel from reversion.

[Taylor]

One thing I wonder about is when I see guys running 48IDA's, on VW's or V8's and they've capped the air horns with those flat foam/metal filters. I tried those a long time ago and immediately took them off. I didn't realize it at the time, but how do those allow for fuel stand off/reversion that happens with Webers on VW? They can't.

Ding ding ding!

My buddy was dialing in/jetting a fresh 2276 at Gary B's shop a few years ago. He drove it from AZ for the Classic weekend but was endlessly trying to perfect it Anyway, he had those thin little pantyhose type filters over the stacks (no metal or foam). LM2 installed to monitor changes. Same as the video above, he removed the filters and it went lean, go figure. He's never used them since. They may flow air just fine, but not when soaked with fuel from reversion.

The '55 in the video might have gone quicker with the filters on 😂

[Iryanu]

One thing I wonder about is when I see guys running 48IDA's, on VW's or V8's and they've capped the air horns with those flat foam/metal filters. I tried those a long time ago and immediately took them off. I didn't realize it at the time, but how do those allow for fuel stand off/reversion that happens with Webers on VW? They can't.

I had a bad experience with the ITG foam socks that go over the top of velocity stacks. I lost one of my filter top plates so to get me over town I put two of these foam socks on to my Weber IDFs, one bank only.

My god, the car ran like absolute crap, stuttering and bunny-hopping and car was sluggish. I was sure I'd broken something, stopped in a pub car park, took off the foam filters, fired it back up and all the symptoms just went away, back to full power. Blew my mind they could make it run that bad, and that was with just two on! I can't imagine how bad it would be with all 4 stacks covered, it was smothering the engine.

These were the offending articles:

http://www.demon-tweeks.co.uk/motorsport/ram-pipes-filter-socks/itg-ram-pipe-trumpet-filter-sock

My brother had four on his mk1 golf 16v and the guy at the rolling road told him he wouldn't tune it with them on as they are known to be utter sh*te!

Live and learn, expensive mistake purchase at £20 per sock!

He runs his trumpets OPEN and has done for the last 7 years I guess, they are directly behind the radiator grille at the front of the car pointing forward. Never had a problem.

I'd run mine open but the baseplates for the filters are part of the cb hex linkage and it would just look daft with the baseplate and no filter. Maybe when I finally get some IDAs....

[Jeff68]

Being aware of how important the fuel stand off is in and above the stacks led me to think that the Berg stacks and filters would work and be a good solution for filters on IDA's.  I also wanted everything to fit under the decklid which I think the Berg's stuff might. When I was ordering some jets and miscellaneous parts from Gary B last year I asked him about them. He really didn't say much about them other than he wasn't sure if they still had them and wasn't sure if they fit under the decklid either. If I had an extra $400 lying around maybe I would try them.....

[Andrew]

I think K&N's 83mm might fit providing short manifolds are installed and the deck lid is stood off at the top, tho I agree upper standoffs aren't to everyone's tastes and let's not go into top versus bottom deck lib stand offs as that's a completely different can of worms....

Another possible solution is to speak to K&N and get something 'custom' made up, this isn't as mad an idea as it first sounds as they do seem to have a custom service - http://www.knfilters.com/custom_air_filters.htm

[UltraOrange67-2443]

http://www.knfilters.com/search/product.aspx?prod=56-1230

Available in 3 heights.

[Andrew]

http://www.knfilters.com/search/product.aspx?prod=56-1230

Available in 3 heights.

Anyone any experience with these?

[Andrew]

Just bumping this back to the top as I'm starting to think about what to do on this one again.

Would the K&N be OK with fuel reversion?

  thanks,

Andrew

[Andrew]

OK, so these are about the only filter I can find that won't get soaks by fuel reversion.



Anyone use them?

  thanks,

Andrew

[UltraOrange67-2443]

Just bumping this back to the top as I'm starting to think about what to do on this one again.

Would the K&N be OK with fuel reversion?

  thanks,

Andrew